JP2019156059A - Lane deviation prevention control device - Google Patents

Abstract

To suppress the intervention of a lane deviation prevention control against the driver's steering intention toward the deviation in the curve-outward direction when passing through a curve during a towed-travel while connecting a towed vehicle, thus to reduce the discomfortness for the driver while securing safety.SOLUTION: In a case where a towed-travel determination section 17 determines that an own vehicle is towed-traveling while connecting a trailer on the rear side, when a curve entrance state determination section 18 determines that a curve entrance state of the own vehicle is safe and a curve outside deviation determination section 19 determines that the own vehicle deviates from a partition line on the outside of a curve, a lane deviation allowance instruction section 21 instructs a lane deviation prevention control section 16 to execute a lane deviation prevention control, which tolerates the deviation from the partition line on the outside of the curve of the own vehicle, of up to a deviation allowance calculated in a deviation allowance calculation section 20.SELECTED DRAWING: Figure 4

Description

  The present invention relates to a lane departure prevention control device that prevents a departure from a lane in which a host vehicle travels.

  A vehicle such as an automobile is equipped with a steering device such as an electric power steering device capable of controlling a steering angle via an electric motor, and a driver's steering operation based on an external environment around the vehicle recognized by a camera, a radar device, or the like. Steering support control for assisting is known.

  As one of the steering assist controls, there is a lane departure prevention control for preventing a departure from the traveling lane of the host vehicle. However, depending on the shape of the traveling path, the execution of the lane departure prevention control may be changed and the driver may feel uncomfortable. There is a case.

  For this reason, for example, in Patent Document 1, when there is a tendency to deviate in the inner direction of a curved road, and there is an approaching vehicle traveling in the same direction as the own vehicle behind the lane in the deviating direction, A technology that realizes lane departure prevention control that does not give the driver a sense of incongruity by giving a yaw moment to a vehicle and avoiding the departure by giving the yaw moment and then decelerating the vehicle. It is disclosed.

Japanese Patent No. 4380301

  However, when the vehicle is towed with a towed vehicle connected to the rear part of the host vehicle, when passing the curve, the deviation of the towed vehicle to the inside of the curve due to the inner ring difference or the side of the towed vehicle In order to prevent contact with a pedestrian, a two-wheeled vehicle, or the like, the driver may intentionally steer the host vehicle to make a large turn and cause the host vehicle to slightly deviate in the curve outward direction. In such a case, if the lane departure prevention control intervenes against the driver's intention, it not only makes the driver feel uncomfortable but also makes it difficult for the driver to travel on a desired route.

  The present invention has been made in view of the above circumstances, and when passing through a curve in towing traveling with a towed vehicle connected, lane departure prevention control that deviates from the driver's steering intention against deviation in the curve outward direction. It is an object of the present invention to provide a lane departure prevention control device that can reduce the sense of incongruity to the driver while suppressing safety and ensuring safety.

  A lane departure prevention control device according to an aspect of the present invention is a vehicle lane departure prevention control device having a lane departure prevention control unit that executes lane departure prevention control for preventing departure from a lane in which the host vehicle travels. A tow travel determination unit that determines whether the towed vehicle travels by connecting a towed vehicle to the rear part of the host vehicle, and a curve approach that determines whether the approach state of the host vehicle to the curve is safe during the towed traveling A state determination unit, a curve outer departure determination unit that determines whether or not to deviate from a lane marking that is outside the curve among the left and right lane markings that form the lane during the towing, and an outer side of the curve A deviation allowance calculating unit for calculating a deviation allowance that defines an allowable limit of the deviation amount of the own vehicle from the lane marking, and an approach state of the own vehicle to the curve is determined to be safe, and the own vehicle is Outside the curve When it is determined that the vehicle departs from the lane line, the lane departure prevention control unit is allowed to perform the lane departure prevention control by allowing the vehicle to deviate from the lane line outside the curve to the deviation allowance. A lane departure allowance instruction unit for instructing.

  According to the present invention, when passing a curve by towing traveling with a towed vehicle connected, the intervention of the lane departure prevention control that is contrary to the driver's steering intention with respect to the deviation to the outside of the curve is suppressed, and safety is ensured. It is possible to reduce a sense of incongruity to the driver while ensuring the above.

Configuration diagram of vehicle travel control system Explanatory diagram showing the running state closer to the inside of the curve when towing the trailer Explanatory drawing showing the running state that allows deviation to the outside of the curve when towing the trailer Block diagram showing the functional configuration of the lane departure prevention control device Explanatory diagram showing a characteristic example of the curve entry speed threshold Flow chart of lane departure prevention control

  Embodiments of the present invention will be described below with reference to the drawings. In FIG. 1, reference numeral 1 denotes a vehicle such as an automobile, and includes a hitch 2 for connecting a towed vehicle (trailer) 100 to the rear part of the vehicle body. The vehicle (own vehicle) 1 can travel while towing the trailer 100 by connecting the joint 101 of the trailer 100 to the hitch ball 2 a of the hitch 2.

  The traveling of the host vehicle 1 is controlled by a traveling control system including a plurality of control devices, and performs driving support for the driver even when the trailer 100 is towed. Each control device constituting the travel control system of the vehicle 1 is configured with a microcomputer as a center, and mainly includes an external environment recognition device 11, an occupant state detection device 12, a navigation device 13, a drive control device 14, and a steering assist control device 15. A communication bus 50 forming an in-vehicle network is connected to be capable of bidirectional communication.

  The external environment recognition device 11 includes detection information of objects around the vehicle by various sensors that detect objects around the vehicle such as cameras and radar devices, traffic information acquired by infrastructure communication such as road-to-vehicle communication and vehicle-to-vehicle communication, Positioning information of own vehicle position based on signals from GPS satellites, map information from navigation device 13, for example, road shape data such as road curvature, lane width, shoulder width, road azimuth, and sections that divide lanes The external environment around the host vehicle is recognized based on high-definition map information including travel control data such as line type and number of lanes.

  In the present embodiment, the external environment recognition device 11 recognizes the external environment around the vehicle by adding map information, traffic information, and the like from the navigation device 13 mainly by image recognition processing by a vehicle-mounted camera. The recognition information outside the host vehicle by the external environment recognition device 11 is sent to the drive control device 14 for steering control such as automatic traveling and follow-up traveling along the route, and brake control for preventing collision with an obstacle. Used as control data.

  As a vehicle-mounted camera, the host vehicle 1 is equipped with a front camera 3 that images a front region outside the vehicle, a rear camera 4 that images a rear region of the host vehicle 1, and an in-vehicle camera 5 that images a driver's state. Each image captured by the front camera 3 and the rear camera 4 is sent to the external environment recognition device 11 for processing, and an image captured by the in-vehicle camera 5 is sent to the occupant state detection device 12 for processing.

  In the present embodiment, the front camera 3 is a stereo camera composed of two cameras 3a and 3b that capture the same object from different viewpoints (hereinafter, the front camera 3 is appropriately selected as the stereo camera 3). May be described). The two cameras 3a and 3b constituting the stereo camera 3 are shutter-synchronized cameras having an image sensor such as a CCD or a CMOS. For example, a predetermined baseline length is provided in the vicinity of a room mirror inside the front window in the upper part of the vehicle interior. It is fixed and arranged with.

  The external environment recognition device 11 obtains a pixel shift amount (parallax) between corresponding positions of the left and right images by stereo matching processing for a pair of stereo images in the traveling direction of the host vehicle 1 captured by the stereo camera 3, A distance image is generated by converting the shift amount into luminance data or the like. The point on the distance image is a point in the real space in which the vehicle width direction of the own vehicle 1, that is, the left-right direction is the X axis, the vehicle height direction is the Y axis, and the vehicle length direction, that is, the distance direction is the Z axis, based on the principle of triangulation. As a left and right dividing line that forms a lane in which the host vehicle 1 travels, white lines, obstacles such as guardrails and side walls on the side of the road, a preceding vehicle that travels in front of the host vehicle 1, and the like are three-dimensionally displayed. Be recognized.

  A white line as a lane marking forming a lane can be recognized by extracting a point group that is a candidate for a white line from an image and calculating a straight line or a curve connecting the candidate points. For example, in a white line detection region set on an image, an edge whose luminance changes more than a predetermined value is detected on a plurality of search lines set in the horizontal direction (vehicle width direction), and one set of white lines is set for each search line. A start point and a white line end point are detected, and an intermediate region between the white line start point and the white line end point is extracted as a white line candidate point.

  Then, the time series data of the spatial coordinate position of the white line candidate point based on the vehicle movement amount per unit time is processed to calculate a model that approximates the left and right white lines, and the white line is recognized by this model. As an approximate model of the white line, an approximate model obtained by connecting linear components obtained by the Hough transform, or a model approximated by a curve such as a quadratic equation can be used.

For example, when a white line is approximated by a quadratic curve, the least square method is applied to the data point group of white line candidate points, and the white line can be represented by a quadratic curve as shown in the following equation (1). . Here, the left and right white lines are represented by the expression (1), but in detail, the coefficients A, B, and C in the expression (1) are obtained for each of the left and right white lines.
X = A · Z ² + B · Z + C (1)

  Coefficients A, B, and C in equation (1) represent lane path components formed by white lines. The coefficient A represents the curvature component of the lane, the coefficient B represents the yaw angle component of the lane with respect to the own vehicle 1 (the angle component between the longitudinal axis of the own vehicle 1 and the tangent to the lane), and the coefficient C represents the lane with respect to the own vehicle 1. Represents the position component (lateral position component) in the horizontal direction (X-axis direction).

  In this embodiment, an example of recognizing a white line of a road as a lane line forming a lane will be described. However, the lane line is not limited to a white line, and lane information acquired from map data or A line set based on position information of the host vehicle 1 may be used.

  The occupant state detection device 12 detects the state of the driving driver from the image of the driver imaged by the in-vehicle camera 5, and determines whether or not the driver state is normal. For example, a change in the driver's line-of-sight behavior or a change in pupil area is detected from the captured image of the in-vehicle camera 5, and based on these changes, it is determined whether or not the driver is awake.

  For example, when the driver's line-of-sight behavior is detected to determine the driver state, the virtual image on the cornea is detected as a reference based on the pupil center as the eye moves. Then, the variation in the driver's line-of-sight behavior with respect to the preceding vehicle or the like detected by the front camera 3 is evaluated to determine whether or not the driver is awake.

  When determining the driver state from the change in the pupil area of the driver, the reduction rate of the pupil area of the driver in the captured image of the in-vehicle camera 5 is calculated. Then, when the time during which the reduction rate of the pupil area exceeds the threshold within a predetermined time becomes equal to or greater than a certain value, it is determined that the driver's arousal level has decreased.

  The navigation device 13 includes a map database 13a, and measures the position of the host vehicle 1 based on signals from a plurality of navigation satellites such as GPS satellites and signals from in-vehicle sensors (gyro sensors, vehicle speed sensors, etc.). Match with 13a. And based on the positional information on a map and the traffic information acquired by infrastructure communication, such as road-to-vehicle communication and vehicle-to-vehicle communication, driving route guidance and traffic information are displayed on a display device (not shown) and presented to the driver. .

  In addition to the map data for navigation that is referred to when displaying the route guidance for the driver and the current position of the vehicle, the map database 13a is used for driving control that is referred to when performing driving support control including automatic driving. High-definition map data is stored.

  In the map data for navigation, the previous node and the next node are linked to the current node through links, and each link has traffic lights, road signs, buildings, etc. Information about is stored.

  On the other hand, high-definition map data for traveling control has a plurality of data points between a node and the next node. The data points include road shape data such as the curvature, lane width, and shoulder width of the road on which the vehicle 1 is traveling, and data for driving control such as road azimuth, road white line type, and number of lanes. It is held together with attribute data such as reliability and date of data update.

  The drive control device 14 controls the engine, the automatic transmission, the brake device, and the like based on signals from various sensors and various control information transmitted via the communication bus 50. Here, the drive control device 14 is a generic term for a group of devices that individually control the engine, the automatic transmission, and the brake device.

  Engine control includes, for example, fuel injection control, ignition timing control, electronic control throttle valve based on intake air amount, throttle opening, engine water temperature, intake air temperature, air-fuel ratio, crank angle, accelerator opening, and other vehicle information. The control such as the opening degree control is executed mainly.

  As transmission control, the hydraulic pressure supplied to the automatic transmission is controlled in advance based on signals from sensors for detecting the shift position, vehicle speed, etc. and various control information transmitted via the communication bus 50. The automatic transmission is controlled in accordance with the changed transmission characteristics.

  Also, as the brake control, for example, a four-wheel brake device (not shown) is controlled independently of the driver's brake operation based on the brake switch, four-wheel wheel speed, steering wheel angle, yaw rate, and other vehicle information. To do. Further, the brake fluid pressure of each wheel is calculated based on the brake force of each wheel, and antilock / brake control, side slip prevention control, and the like are performed.

  The steering assistance control device 15 executes driving assistance control for assisting automatic driving of the host vehicle 1 and driving of the driver. For example, a target course on which the vehicle 1 travels is set based on the recognition result of the external environment, steering control is performed so as to travel following the target course, assist torque for assisting the steering operation of the driver, and further automatic steering Torque is output via an electric power steering (EPS) device 30.

  Note that the EPS device 30 is a well-known device having an electric motor connected to a steering mechanism such as a rack and pinion type and a control unit that drives and controls the electric motor, and detailed description thereof is omitted.

  The target course in the steering control of the steering assist control device 15 is set based on the recognition result of the external environment by the external environment recognition device 11. For example, in the lane keeping control for keeping the host vehicle 1 at the center of the lane, the center position in the width direction of the left and right white lines of the host vehicle 1 is set as the target course.

  The steering assist control device 15 sets a target steering angle that matches the center position in the vehicle width direction of the host vehicle 1 with the target course, and the motor drive current of the EPS device 30 is set so that the steering angle of the steering control becomes the target steering angle. To control. The target course may be set not by the steering assist control device 15 but by another control device such as the external environment recognition device 11.

  In addition to the lane keeping control for keeping the host vehicle 1 at the center of the lane, the steering assist control device 15 executes lane departure prevention control for preventing a departure from the lane of the host vehicle 1. Specifically, the steering assist control device 15 is based on the information from the external environment recognition device 11 and the driving state of the host vehicle 1, and the left and right dividing lines (left and right white lines) in which the traveling direction of the host vehicle 1 forms a lane. ), The estimated lane departure time Ttlc until the host vehicle 1 crosses the lane marking (white line) in the departure direction is calculated, and the estimated lane departure time Ttlc is the vehicle speed of the host vehicle 1. When the value is equal to or less than the threshold value determined by V and the curvature κ of the lane, the lane departure prevention control is started.

  Here, in the case of passing the curve by towing traveling with the trailer 100 connected to the rear portion of the host vehicle 1, the driver may intentionally steer the host vehicle 1 so as to go out of the curve and make a large turn. is assumed. Therefore, the steering assist control device 15 reduces the sense of discomfort to the driver while ensuring safety by changing the intervention mode of the lane departure prevention control between the curve inner direction and the curve outer direction.

  That is, as shown in FIG. 2, when there is a possibility that the host vehicle 1 may deviate from the lane marking Lin that is inside the curve, the steering assist control device 15 intervenes the lane departure prevention control as in the conventional case, and the lane To prevent deviations from On the other hand, as shown in FIG. 3, for the lane line Lout that is outside the curve, the steering assist control device 15 may diverge from the lane line Lout depending on the situation even when there is a risk of deviating from the lane line Lout. Deviation of the vehicle 1 from Lout is allowed within a predetermined range.

  For this reason, as shown in FIG. 4, the steering assist control device 15 responds to the lane departure prevention control unit 16 that executes normal lane departure prevention control for preventing departure from the lane according to the situation during towing. And a functional unit for allowing deviation from the lane marking that is outside the curve. Specifically, in addition to the normal lane departure prevention control unit 16, the steering assist control device 15 includes a tow travel determination unit 17, a curve approach state determination unit 18, a curve outer departure determination unit 19, a deviation allowable amount calculation unit 20, A lane departure allowance instruction unit 21 is provided.

Specifically, the lane departure prevention control unit 16 calculates a target yaw rate γtgt that is a target turning amount for preventing departure from the lane. The target yaw rate γtgt is calculated by adding the yaw rate γturn that causes the host vehicle 1 to suppress the lane departure and the yaw rate γlane according to the curvature of the lane, as shown in the following equation (2).
γtgt = γturn + γlane (2)

In the equation (2), the yaw rate γturn that causes the behavior of suppressing the lane departure is, for example, the yaw angle (to the lane yaw angle) θyaw with respect to the lane of the host vehicle 1 as described in the following equation (3), It can be calculated based on the lane departure estimated time Ttlc.
γturn = θyaw / Ttlc (3)

The yaw rate γlane corresponding to the curvature of the lane is, for example, the vehicle speed V of the host vehicle 1 detected by the vehicle speed sensor 6 and the curvature of the lane acquired by the external environment recognition device 11 as shown in the following equation (4). It can be calculated based on κ.
γlane = κ · V (4)

  Further, the lane departure prevention control unit 16 calculates a target steering torque Ttgt for realizing the target yaw rate γtgt, and outputs the target steering torque Ttgt as an instruction torque for the EPS device 30. The EPS device 30 controls the drive current of the electric motor so that the steering torque output from the steering mechanism becomes the target steering torque Ttgt.

The target steering torque Ttgt is, for example, a feedback torque Tfb based on a deviation between the target yaw rate γtgt and the actual yaw rate γ of the host vehicle 1 detected by the yaw rate sensor 7, vehicle speed V and lane, as shown in the following equation (5): The feedforward torque Tff obtained by torque-converting the yaw rate γlane based on the curvature κ of the current with a predetermined conversion gain is added.
Ttgt = Tfb + Tff (5)

  The tow travel determination unit 17 detects whether the trailer 100 is connected to the rear part of the host vehicle 1 based on the rear image of the host vehicle 1 captured by the rear camera 4, and the trailer 100 is connected. Judge whether or not you are driving. For example, the presence of an object larger than a predetermined size is recognized in the image captured by the rear camera 4, and the area of the object in the image changes more than a predetermined value with respect to the steering angle while the host vehicle 1 is traveling. If not, it can be determined that the trailer 100 is connected to the rear portion of the host vehicle 1 and the vehicle is towing.

  Note that the function of the tow travel determination unit 17 may be provided in the external environment recognition device 11 without being provided in the steering assist control device 15.

  In this case, for example, an electrical switch that is turned on when the joint 101 of the trailer 100 is connected to the hitch 2 may be provided, and the connection of the trailer 100 may be detected by turning on or off the switch. The trailer that can be coupled may be limited by the coupling mechanism. In the present embodiment, since the connection of the trailer 100 is detected from the image of the rear camera 4, the restriction on the trailer side to be connected can be reduced.

  The curve approach state determination unit 18 examines the state of the driver driving the host vehicle 1, the vehicle speed before entering the curve, and the brake operation state of the driver, and determines whether the curve approach state of the host vehicle 1 during towing is safe. To do. When the driver's state detected by the occupant state detection device 12 is not normal, it is determined that the host vehicle 1 cannot safely travel the curve, and notifies the lane departure prevention control unit 16 to prepare for lane departure and drive control. The process shifts to evacuation control via the device 14.

  When the state of the driver detected by the occupant state detection device 12 is normal, at least a threshold (curve entry speed) at which the vehicle speed (speed before entering the curve) V of the host vehicle 1 before entering the curve can safely travel on the curve. It is determined whether or not the approach state of the host vehicle 1 to the curve is safe depending on whether or not the threshold value is Vsafe or less. When the curve entry speed V is equal to or less than the curve entry speed threshold Vsafe, it is determined that the vehicle 1 is in a curve entry state and the curve can be traveled safely.

  On the other hand, if the speed V before the curve entry exceeds the curve entry speed threshold value Vsafe, the driver further operates the brake to make the vehicle speed V of the host vehicle 1 less than the curve entry speed threshold value Vsafe. Check if it has occurred. Then, when deceleration that causes the pre-curve entry speed V to be equal to or lower than the curve entry speed threshold Vsafe is generated by the brake operation, it is determined that the host vehicle 1 can travel on the curve safely.

The curve approach speed threshold value Vsafe defines an upper limit of the speed at which the curve κ can be safely traveled. For example, assuming a steady circular turn with a curvature radius R (R = 1 / κ) at a vehicle speed V, and the lateral acceleration Ac in the following equation (6) is a safety value (constant) in road design, a curve approach The speed threshold value Vsafe has a characteristic as shown in FIG. 5 with respect to the curvature κ.
1 / R = Ac × (1 / V ² ) (6)

  The curve outside departure determination unit 19 determines whether or not the host vehicle 1 departs from a lane marking that is outside the curve during towing. As described above, whether or not the own vehicle 1 departs from the lane (lane line) can be determined by the lane departure estimation time Ttlc, with respect to the lane line whose traveling direction is outside the curve. If the lane departure estimated time Ttlc is less than or equal to the threshold value, it is determined that the host vehicle 1 departs from the lane marking that is outside the curve.

  The deviation allowance calculation unit 20 defines a deviation allowance that defines an allowable limit of the deviation amount of the host vehicle 1 with respect to a departure from a lane line that is outside the curve of the host vehicle 1 due to the intentional steering operation of the driver. The capacity Xover is calculated. The deviation allowable amount Xover may be a value separated from the lane marking on the outside of the curve by a certain distance in the vehicle width direction (for example, about 3 m from the white line on the deviation side), the curvature of the curve, the vehicle 1 and the trailer 100. May be calculated based on at least one of the total length of the connected vehicles including

  When the deviation allowance is calculated based on the curvature of the curve and the total length of the connected vehicle, the deviation allowance is increased as the curvature of the curve is increased, and the allowance is increased as the total length of the connected vehicle is increased. The total length of the connected vehicle is acquired based on the known total length of the host vehicle 1 and the total length of the trailer 100 by user input or the like.

  However, if there are guardrails, side walls, etc. on the outside of the curve, or there is a further lane adjacent to the lane marking on the outside of the curve, the adjacent lane faces the host vehicle 1 and travels. If the vehicle is in the opposite lane of another vehicle, Xover = 0 and no deviation is allowed.

  The lane departure allowance instruction unit 21 instructs the lane departure prevention control unit 16 when the vehicle 1 is determined to be safe and the vehicle 1 departs from a lane that is outside the curve. An instruction is given to execute the lane departure prevention control while allowing the departure from the lane marking on the outside of the curve of the vehicle 1 to the allowable departure amount Xover.

  Lane departure prevention control that allows departure of a predetermined range is realized, for example, by correcting the estimated lane departure time Ttlc in equation (3) for the yaw rate γturn that causes the lane departure suppression behavior of the host vehicle 1 can do. For example, by setting a correction coefficient based on the deviation allowable amount Xover and the vehicle speed V and multiplying the correction coefficient by the lane departure estimated time Ttlc, the lane departure estimated time when the deviation is allowed can be corrected. In other words, a lane line in which the lateral position of the white line is offset by the deviation allowance Xover is set with respect to the white line of the road, and lane departure prevention control is performed on the offset lane line. I can say that.

  Next, the lane departure prevention control in the steering assist control device 15 will be described with reference to the flowchart of FIG.

  In this lane departure prevention control, in the first step S1, the steering assist control device 15 detects the presence / absence of a towed vehicle (trailer 100) based on the image captured by the rear camera 4, and the trailer 100 is turned off in step S12. It is determined whether or not the tow traveling is connected.

  When the vehicle 1 is traveling alone without connecting the trailer 100, the process proceeds from step S2 to step S12. In step S12, the steering assist control device 15 determines whether or not the host vehicle 1 departs from the lane, and when it is determined to deviate from the lane, the steering assist control device 15 executes normal lane departure prevention control for the lane on the departure side.

  On the other hand, if the trailer 100 is connected and the vehicle is towing, the process proceeds from step S2 to step S3, and the steering assist control device 15 calculates the curvature of the traveling path of the host vehicle 1 (the lane in which the host vehicle 1 travels). Get κ. In the present embodiment, the curvature κ of the traveling path is acquired for each of the left and right dividing lines (white lines) forming the lane. When the white line is approximated by the above-described equation (1), the curvature of each of the left and right white lines can be obtained based on the coefficient A of the quadratic curve in the equation (1).

  When high-definition map data is held in the map database 13a, the curvature and lane width of the road at the current position of the host vehicle 1 are read from the map database 13a, and the curvatures of the left and right lane markings are obtained. Anyway.

  Thereafter, the process proceeds from step S3 to step S4, and it is checked whether or not the curvature κ acquired in step S3 is equal to or greater than the threshold value κs. The threshold value κs is a threshold value for determining whether or not the traveling path is a curved path. For example, a curvature radius of about 150 m or less is assumed as the curved path.

  When it is determined in step S4 that the curvature κ is less than the threshold κs and the road is a straight road, the process proceeds from step S4 to step S12, and normal lane departure prevention control can be executed. On the other hand, if it is determined in step S4 that the curvature κ is equal to or greater than the threshold κs and the road is a curved road, the process proceeds from step S4 to step S5, and the steering assist control device 15 determines the driver state based on information from the occupant state detection device 12. Check if is normal.

  If any abnormality is detected in the driver by the occupant state detection device 12 and the driver state is not normal, the process proceeds from step S5 to step S12 described above, and normal lane departure prevention control can be executed in preparation for lane departure. And On the other hand, if the driver state is normal, the process proceeds from step S5 to step S6.

  In step S6, it is checked whether or not the speed V before entering the curve of the host vehicle 1 is equal to or lower than a curve entry speed threshold Vsafe that is a threshold at which the vehicle can safely travel on the curve. When V> Vsafe, the process proceeds from step S6 to step S7, and it is checked whether or not the deceleration state before the vehicle enters the vehicle 1 (pre-curve deceleration state) satisfies a preset deceleration condition. If the pre-curve deceleration state does not satisfy the deceleration condition, the routine proceeds from step S7 to step S12, where normal lane departure prevention control is made executable.

  The deceleration condition for the pre-curve deceleration state is a condition in which the brake switch is on and the driver is surely stepping on the brake pedal, and a deceleration is obtained that allows the pre-curve entry speed V to be less than or equal to the curve entry speed threshold Vsafe. It is. However, the deceleration at this time is desirably a deceleration of about 0.1 G or less, for example, with the upper limit being a deceleration that does not cause instability of the vehicle behavior.

  On the other hand, if V ≦ Vsafe in step S6, or if the deceleration condition for the pre-curve deceleration state is satisfied in step S7, the process proceeds from step S6 or step S7 to step S8. In step S8, the steering assist control device 15 determines whether or not the host vehicle 1 may deviate from a lane marking that is outside the curve.

  If it is determined that there is no possibility that the host vehicle 1 deviates from the lane line that is outside the curve, the process proceeds from step S8 to step S12, and normal lane departure prevention control is provided in preparation for deviation from the lane line that is inside the curve. Is made executable. If it is determined that the host vehicle 1 may deviate from the lane marking on the outside of the curve, the process proceeds from step S8 to step S9.

  In step S9, the steering assist control device 15 checks whether the departure destination is an oncoming lane or whether there is an obstacle such as a guardrail or a side wall at the departure destination. When the departure point is the oncoming lane or there is an obstacle such as a guardrail or a side wall at the departure point, the process proceeds from step S9 to step S12, and normal lane departure prevention control can be executed.

  On the other hand, if the departure point is not an oncoming lane and there is no obstacle such as a guardrail or a side wall at the departure point, the process proceeds from step S9 to step S10, and the deviation allowable amount Xover from the lane marking outside the curve is calculated. . In step S11, lane departure prevention control is performed in consideration of the deviation allowable amount, and deviation from the lane marking on the outside of the curve of the host vehicle 1 is allowed up to the deviation allowable amount Xover.

  As described above, in this embodiment, when there is a possibility of deviating in the curve inward direction when passing the curve by towing traveling with the trailer 100 connected, the lane departure prevention control is performed as in the conventional case. While intervening, there is a possibility of deviating outside the curve, it is judged whether the curve approaching state is safe, and if it is judged safe, deviating from the demarcation line outside the curve An allowable amount Xover is allowed, and the intervention of the lane departure prevention control that is contrary to the driver's steering intention with respect to the departure in the curve outward direction is suppressed. Accordingly, it is possible to reduce a sense of incongruity to the driver while ensuring safety, and it is possible to travel on a route desired by the driver.

DESCRIPTION OF SYMBOLS 1 Own vehicle 2 Hitch 3 Front camera 4 Rear camera 5 In-vehicle camera 6 Vehicle speed sensor 7 Yaw rate sensor 11 External environment recognition apparatus 12 Occupant state detection apparatus 13 Navigation apparatus 13a Map database 14 Drive control apparatus 15 Steering support control apparatus 16 Lane departure prevention control Section 17 Traction travel determination section 18 Curve approach state determination section 19 Curve outside departure determination section 20 Deviation allowance calculation section 21 Lane departure allowance instruction section 30 EPS device 100 Trailer

Claims (6)

A lane departure prevention control device for a vehicle having a lane departure prevention control unit that executes lane departure prevention control for preventing departure from a lane in which the host vehicle travels,
A towed traveling determination unit that determines whether the towed vehicle travels by connecting a towed vehicle to the rear of the host vehicle;
A curve approach state determination unit that determines whether the approach state to the curve of the host vehicle is safe during the towing,
A curve outside deviation determining unit that determines whether or not to deviate from the lane marking that is outside the curve among the left and right lane markings that form the lane during the towing;
A deviation allowance calculating unit that calculates a deviation allowance that defines an allowable limit of the deviation amount of the vehicle from the lane marking that is outside the curve; and
When it is determined that the approach state of the host vehicle to the curve is safe and the host vehicle departs from a lane line that is outside the curve, the lane departure prevention control unit is provided with a partition that is outside the curve. A lane departure prevention control device, comprising: a lane departure allowance instruction unit that instructs to execute the lane departure prevention control while allowing a departure of the host vehicle from a line to the allowable departure amount.   The deviation allowance calculation unit calculates the deviation allowance based on at least one of the curvature of the curve and the total length of the coupled vehicle including the host vehicle and the towed vehicle, and the curvature of the curve increases as the curvature of the curve increases. 2. The lane departure prevention control device according to claim 1, wherein the deviation allowance is increased, and the deviation allowance is increased as the total length of the coupled vehicles is increased.   2. The lane departure according to claim 1, wherein the deviation allowable amount calculation unit calculates the deviation allowable amount as a value that is a fixed distance away from a lane marking that is outside the curve in a vehicle width direction. Prevention control device.   The curve entry state determination unit determines whether the entry state to the curve is safe based on whether or not at least the speed before entering the curve is equal to or less than a curve entry speed threshold set based on the curvature of the curve. The lane departure prevention control device according to any one of claims 1 to 3, wherein the lane departure prevention control device is determined.   The lane departure prevention control device according to claim 4, wherein the curve approach speed threshold is a threshold that gives a constant acceleration to the curvature of the curve in a steady circle turn.   The said tow travel judgment part judges the tow run which connected the said towed vehicle based on the image of the back of the own vehicle imaged with the camera. The lane departure prevention control device described.

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